Engine starter



April 1960 J. c. TROTTER ETAL 2,932,292

ENGINE STARTER Filed June 12, 1956 J R v m#. r y W M mfk/r d vtm W m can v 4 2% W 1 W a z .J. I w Ma).

United ENGINE STARTER Application June 12, 1956, Serial No. 590,965

2 Claims. (Cl. 123179) This invention relates to new and useful improvements in engine starters, and more particularly to a starter for small internal combustion engines such as are commonly used on lawn mowers and the like, and adapted to be started by rapidly revolving the drive shaft thereof. Still more specifically, our starter is designed for use in connection with engines of the character described which are provided with the usual rope starter constituting a drum fixed to the drive shaft and about which a rope may be wound, whereupon a sharp pull on said rope will revolve the drum and drive shaft rapidly.

The principal object of the present invention is the pro vision of an engine starter of the character described comprising a shank adapted to be chucked in an ordinary hand drill motor, and provided with a head adapted to engage non-rotatively in an engine starter drum as described, whereupon operation of said motor will turn said drum and the engine drive shaft.

Another object is the provision of an engine starter of the class described which is adaptable to be either power driven, as outlined above, or manually operated.

A further object is the provision of an engine starter of the class described which is readily adjustable to engage operatively in starter drums of various diameters and axial lengths.

Other objects are simplicity and economy of structure, efiiciency and dependability of operation, and applicability to a wide variety of engines.

With these objects in view, as well as other objects which will appear in the course of the specification, reference will be had to the drawing wherein:

Fig. 1 is a side elevational view of an engine starter embodying the present invention, shown in operative relationship to an internal combustion engine,

Fig. 2 is an enlarged, fragmentary sectional view, taken on line 11-11 of Fig. 1, with parts left in elevation and broken away, and

Fig. 3 is a slightly irregular sectional view taken on line IIIIII of Fig. 2.

Like reference numerals apply to similar parts throughout the several views, and the numeral 2 applies to a small internal combustion engine having a drive shaft 4 to which is afiixed a pulley 6 which carries a belt 8 by means of which the engine is operatively connected to the parts it is to drive. It will of course be understood that the engine is adapted to be started by rotating drive shaft 4. The outer end portion 10 of said drive shaft is reduced in diameter and threaded, and a rope starter drum 12 is mounted fixedly thereon. As shown, said drum constitutes a cup-shaped member having a cylindrical wall 14 concentric with the drive shaft, and an end wall 16 disposed between a shoulder 18 formed by reducing the diameter of the end portion 10 of the shaft and a nut 20 threaded on said end portion of the shaft. A lock washer 22 is disposed between nut 20 and drum wall 16 to assist in securing the drum against rotation relative to the shaft. Portion 10 of the drive shaft normally extends outwardly from the nut to some degree.

tes Patent Cylindrical wall 14 of the drum is notched inwardly from the open end thereof, as indicated at 24, this notch being inclined toward end wall 16 in the direction of rotation of the drive shaft, which is clockwise as viewed from the left in Figs. 1 and 2.

In the normal use of this starter drum, a rope having a knot or other enlargement at one end thereof is laid in notch 24, with the knot inside the drum, and the body of the rope is wrapped externally around the drum. A sharp pull on the free end of the rope will therefore rotate the drum to start the engine. The drum is ordinarily provided at its open end with an outturned lip 26, and the closed end of the drum is ordinarily disposed against pulley 6, or against a flywheel or the like, these provisions serving to prevent the rope from slipping 01f of the ends of the drum.

The starter forming the subject matter of this invention comprises a rod-like shank 28 one end of which is adapted to be gripped in the chuck 30 of an ordinary electric hand drill motor 32, such motors ordinarily being equipped with a hand grip 34 and trigger-type switch 36, and being supplied with electric current through a cable 38. The other end of shank 28 carries a head 40 adapted to be interengaged with starter drum 12. Said head includes an open-ended tubular socket 42 rigidly fixed to the end of shank 28 in coaxial relation therewith, a sleeve 44 carried slidably on said socket, and a radially extending arm 46 rigidly fixed to said sleeve. Said sleeve is rendered longitudinally adjustable along socket 42, and locked against rotation thereon, by a screw 48 extending through a hole 50 in said sleeve and threaded selectively into any one of a series of longitudinally spaced apart drilled and tapped holes 52 formed in socket 42.

In use, the shank 28 of the starter is disposed coaxially with engine drive shaft 4 and the open end of socket 42 is fitted over that end portion 10 of said drive shaft which extends outwardly from nut 20, arm 46 extending radially through notch 24 of drum 12. Then when motor 3'2 is started by closing switch 36, the rotary torque of shank 28 will be transmitted through arm 46 to the drum, rotating said drum and drive shaft 4 to start engine 2. The engagement of socket 42 with the drive shaft serves to maintain shank 28 centered relative to the drive shaft. When the engine catches and begins to turn under its own power, drum 12 will turn faster than shank 28, and the inclined wall of drum notch 24 will act as a cam to urge arm 46 and socket 42 outwardly out of engagement with the drum and shaft, thereby preventing possible damage to the parts or injury to the operator.

It will readily be seen that arm 46 is of such a length that it will engage in the rope notches of drums of various diameters. Likewise, variations in the depth of the drum may be compensated by removing screw 48, sliding sleeve 44 along the socket, and reinserting screw 48 in another of holes 52. While the holes 52 actually shown are spaced to accommodate the starter to drums of certain drums which arestandard and widely used, it will be apparent that any number of holes with any desired spacing could be used. It will be seen also that shank 28 could be provided alternatively with a crank or other means permitting manual operation.

While we have shown and described a specific embodiment of our invention, it will be apparent that many minor changes of structure and operation could be made without departing from the spirit of the invention as defined by the scope of the appended claims.

What we claim as new and desire to protect by Letters Patent is:

1. An engine starter for use in connection with an engine adapted to be started by revolving the drive shaft thereof and having a hollow, open-ended drum fixed to said drive shaft concentrically therewith, a free end of said drive shaft being disposedwithin-said drum, and said drum being notched inwardly from the open end thereof, said starter comprising a shank adapted to be rotated by power means and adapted to be-aligned with said-drive shaft to-extend within said rollow drum, and

an arm fixed to said shank and extending radially outwardly therefrom to engage in said drum notch, an opencnded socket being fixed to the end of said shank-coaxially therewith and adapted to fit loosely over t-he'free end of said drive shaft, whereby said shank is maintained substantially coaxially with said drive shaft, and wherein saidarm is adjustably movable longitudinally relative to said shank.

2. An engine starter for use in connection with an engine adapted to be started by revolving the drive shaft thereof and having a hollow, open-ended drum fixed to said drive shaft'concentrically therewith, a free end of saiddrive shaft being disposed within said drum, and said drum being notched inwardly from the open end thereof, said starter comprising a shank adapted to be rotated by power means and adapted to be-aligned with said drive shaft, an open-ended socket fixed to said shank "eoaxiallytherewithand adaptedto extend into said'drurn and to fit loosely over the free end of said drive shaft, a sleeve mounted on said socket for longitudinal sliding movement, means operable to secure said sleeve at various positions along said socket and to secure said sleeve against rotation relative to said socket, and an arm fixed to said sleeve and extending radially therefrom to engage in the notch of said drum.

" References Cited in the file of thispatent UNITED STATES PATENTS 1,313,693 Hucks Aug. 19, 1919 1,540,656 Seppmann June 2, 1925 1,632,300 Le Fever June 14, 1927 2,385,963 Beard Oct. 2, 1945 2,437,305 Nickle Mar. 9, 1948 2,700,968 Me-Elroy Feb. 1, 1955 2,731,007 Benson Ian. 17, 1956 2,804,957 Pcchin Sept. 3, 1 957 2,816;-535 Sells Dec. 17, 1-957 

